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ELECTRICITY 



IN 



COMMON WORDS. 



A POPULAR DESCRIPTION OF THE PROGRESS, DEVELOPMENT 
AND APPLICATION OF ELECTRICITY. 



AVERY D. HARRINGTON, Esq., 
Philadelphia, 



J. CHESTER WILSON, 
Electrical Engineer, Philadelphia. 



1884. 



I 



Entered according to the Act of Congress, in ihe year 1884, by Charles S. Adams, 
in the office of the Librarian of Congress at Washington. 



'tf%°\ 



Philadelphia : — Press of Billstein & Sou, 925 & 927 Filbeit St. 



Table of Contents. 



Page. 

Introduction, 5 

What is Electricity? 11 

Frictional Electricity, 18 

The Grave of Franklin 26 

Galvanic Electricity, 30 

Electro-typing, 35 

Electro-plating and Gilding, 37 

Electric Fuse, 39 

Electric Bells, 41 

Magnetism, » 43 

The Compass, '. 47 

The Telegraph, 49 

Electric Wires, 58 

Telegraph Ocean Cables, 59 

The Telephone, 64 

Electric Light, 78 

Dynamo-Electric Machines, 89 

Gas Lighting, 96 

The Electko-Motor, 104 

Conclusion, 107 




'■>'' i:i ;; 



Introduction. 

SURPRISING would it seem, in this evening part of the 
year 1884, if the pages of this brief volume were to put 
forth the statement, that in addition to the little ride you had 
just taken upon the Electric Railway between points not out 
of sight of each other, you were, before the next year closes, 
to speed across the continent by the same power. Further- 
more, that ere you embarked, in addition to speaking with 
your friend in the far distant city you could recognize not 
only the voice, although but a whisper, but could see his face, 
and this alone through the medium of a feeble earth current 
or of one derived from the air itself by your little thread- 
like wire, which shall stretch its length along over the plains, 
up and down the mountains, through the forest, across the 
deep abyss, through the cable in the river's bed, and feeling 
a thousand differences of temperature on its way. 

Would not the surprise be continued should it be 

stated that if on your journey you suffered delay, by 

(5) 



6 

accident or otherwise, the danger would amount to nothing, for 
along the way automatic acting electric machinery would 
avoid collision, and prevent shock, even if your car should 
roll over the embankment; and that instead of disappointing 
your proposed guest as to the hour of arrival, you would only 
have to ask for the Telephone on the car, and, notwithstanding 
your speed of traveling and without regard to your location, 
you could have perfect facility for conversing with him and 
making a change of engagement; and that this would be 
accomplished without the necessity of metallic connection, 
for the strata of the air would be used. 

Nor would the astonishment be abated if these opening 
pages should assert that successful experiment had been per- 
formed, by which transportation of persons and freight had 
been accomplished in one-tenth the time required by steam ; 
that this statement is accompanied by the apology that only 
partial success had been attained, due to the fact that at this 
rate of speed it would be necessary, in long journeys, to 
take too frequent periodical stops to give passengers opportu- 
nities to breathe ; while with the thorough mastery of these 
electrical appliances it is hoped in the near future to make all 
journeys, except the semi-continental ones, in the time 



7 

absolutely necessary for humanity to " take a breath ;" that the 
journey would be accomplished before the interested traveler 
could read in the morning paper the new promise by Keeley, 
to his stockholders, of the day upon which the public (?) 
exhibition would be given on " Vaporic Force." 

If such should be the prophetic opening of this volume, 
who would dispute the possible realization of these things; 
for if one stood in the gallery at the end of the great arch of 
the Electrical Exhibition, at Philadelphia, recently in such 
eminently successful operation, and reflected for a moment 
upon what was before him, what opinion would he venture as 
to what may not be accomplished within the next ten 
years ? 

With the exception of the large plate machines and 
Rhumkorff induction coils in the interesting exhibit at his 
feet, where else could he rest his eyes upon anything, which, 
in its commercially finished condition, dates back prior to our 
great Centennial year, which now seems but yesterday. 

Would it draw painfully upon the imagination to read 
of any accomplishment in the use of this wonderfol force 
within the next decade of years, starting as it does upon aa 



8 

electrical basis compared with which the entrance of the past 
decade is as almost nothing? 

Only a few details yet remain to be worked out before 
our railway trains will be lit by electric light, and, closely 
following this, heating and many other comforts will no doubt 
be added ; for in this age of travelers, so much of life is spent 
on the cars that they almost become our moving homes, and 
home comforts are demanded. 

Instead of making the work one of speculation or pro- 
phecy, the aim is to give a "popular" rendering of the subject, 
freeing it from the burden of the usual technicalities of the 
science, avoiding as far as possible all scientific expression, and 
adapting the reading to the wants of those who have neither 
the previous preparation, nor the time to read a volume in 
which the subject is treated from a scientific standpoint. 

The object of the v/riters is to simply give a conversational 
knowledge of electricity. 

The history, development, and most important applica- 
tions of it will be traced down to the present. Of course it will 
be quite impossible in the scope of a hand-book to go into 
the details of the science, and explain, or even mention all its 
uses ; but the cardinal principles and their application will be 



9 
considered, as deeply, no doubt, as the casual reader desires. 

The watchword of the nineteenth century is " progress/' 
Hence the field of science has been more carefully cultivated, 
and is producing more abundant fruits and practical results 
to-day, than in all the preceding centuries of the world's his- 
tory. Indeed, there seems to be no avenue which scientists 
have not explored by observation and experiment, the result 
of which has been the grandest development of science, as 
applied to the comfort, convenience, and prosperity of man- 
kind, that the world has ever seen. 

Scientific principles no longer exist in the mind as fancies 
and day dreams, as of old ; but by the intensely practical 
mind of to-day, they are utilized and made the hand-maids 
of prosperity. 

No one department of science has attracted in recent 
years, or is attracting more attention just now, than that of 
electricity. 

The expression in regard to the present adaptation of 
electricity, " It is but in its infancy " has become hackneyed, 
and falls flat in the ears of the toilers in this interesting and 
fascinating field of science, and yet none know so well how 
immeasurable seem the depths unexplored, as the worker 



whose life is made up of one continuous thought as to its 
laws and its possibilities, and doubtless the wisest one of all who 
is tugging away at the curtains which veil the future from him, 
would not stop in his efforts to draw them back, and write its 
history with any anticipation of having the book complete 
and abreast of the present development, as its last pages 
leave his hands for the printer. 



WHAT IS ELECTRICITY? 



LITTLE did Thales of Miletus, Greece, six hundred years 
before the Christian Era, when he rubbed a piece of amber 
and observed it attracted light bodies, think that he had 
discovered the force, the development of which would lie and 
wait so long for the unfolding of its valuable secrets, or that within 
the space of a few decades it would take so great a part in the 
science and commerce of the world. 

His conclusions at that time were* that an unknown spirit or 
element animated the amber, that when rubbed, this spirit was 
aroused, and, leaving the amber, went out after these light parti- 
cles, and returning with them caused them to adhere to the surface. 
The Greek word Electron means amber, and from it we have 
derived our word electricity. 

Theophrastus, a Greek, discovered, some centuries later, that 
the same attractive property resided in a crystal, now thought to be 
the tourmaline. Pliny says that the scientists of his time were well 

acquainted with the attractive power of amber ; and, indeed, 

(ii) 



12 ELECTRICITY 

certain other bodies were known to the ancients to manifest the 
same property, upon being rubbed. 

It will thus be seen that the science of electricity is old in its 
inception, but, as the reader will hereafter discover, it has been 
remarkably slow in its development, and its practical application 
to the wants of mankind has only become an accomplished fact 
during and since the second quarter of the present century. 

Pliny says nothing to warrant the conclusion that the scien- 
tific men of his time had added anything to the knowledge of 
electrical phenomena, possessed by the philosophers of the pre- 
ceding six centuries; and it was not until towards the close of 
the sixteenth century, that the first attempt was made toward a 
classification, or generalization, of electrical phenomena, or mani- 
festations. This attempt was made by Dr. William Gilbert, in a 
treatise on the magnet. 

A century later, Dr. Wall, Boyle, Newton, and others, ascer- 
tained many additional facts, but they were not of such a char- 
acter as to furnish data from which the principles of the science, 
as now understood, could be evolved. 

Not until 1728, was it discovered that electricity would pass 
quite readily through certain bodies. Mr. Stephen Grey, who 
made this discovery, classified bodies into conductors and non- 
conductors. This classification is not now accepted as being abso- 



IN COMMON WORDS. 13 

lutely correct, since all bodies possess the property of transmitting 
electrical force in a greater or less degree. However, for all 
practical purposes the classification is correct, and bodies are called 
conductors and non-conductors. 

Those bodies, which offer but little resistance, such as silver 
and copper, are called good conductors ; and those which offer 
great resistance, as gutta-percha and glass, are termed poor con- 
ductors, or insulators. Hence, for convenience of expression, we 
speak of a current of electricity and electric fluids, though in 
reality there is no such thing. The expression must be under- 
stood as figurative only, as will be presently shown. 

To Du Fay, a French philosopher, belongs the honor of 
discovering two opposite states of electrical excitation ; or, in 
other words, positive and negative electricity. Why there are 
two kinds of electrical force, and why when two bodies are rubbed 
together one will be found to possess positive and the other neg- 
ative electricity ; or why the same body exhibits different kinds 
when rubbed by different substances, we do not know. 

For example, polished glass is electrified positively when 
excited with flannel, but negatively when rubbed with cat's fur ; 
again, rough glass rubbed with flannel is negatively electrified, or 
excited, but positively electrified when rubbed with oiled silk. 

The two kinds are always produced at the same time, and never 



i 4 ELECTRICITY 

exist separately and independently of each other. In other words 
it is impossible to have one without the other. Again all bodies 
cannot be electrified, or excited, with equal facility. When 
they are easily excited, they are called electrics, and are poor 
conductors : when they are hard to excite, they are termed non- 
electrics, and are good conductors. Metals generally are non- 
electrics. 

It is only by actual experiment that we can ascertain when 
a body will produce positive, and when negative, electricity. 
There is no law by which it can be previously determined ; but 
the same kind of electricity will always be produced in the same 
body under the same conditions. 

The peculiar power, called electricity, is known to us only 
by its effects. • Many theories, respecting its nature, have been 
advanced, but only three can be briefly noticed, viz : that of 
Du Fay and Symmer, that of Franklin, and the dynamic theory 
as taught by Tyndall, Grove, and others. 

Du Fay and Symmer supposed electricity to be an infinitely 
thin fluid, pervading all bodies, and composed of two elements, 
each having distinct and opposite properties. These elements 
they called vitreous and resinous electricities. Each was sup- 
posed to balance or hold the other in check, when combined, 
repose being the result. When, however, a separation between 



IN COMMON WORDS. 15 

these elements took place, each became active. This theory 
attributes electrical excitation to a separation and taking away of 
one of the elements, leaving the other in excess, or unbalanced. 

The theory of Franklin supposes the existence of a single 
fluid of extreme thinness and elasticity, and distributed equally 
throughout all substances. This fluid is thought to repel its own 
particles, but to attract all other matter. If distributed in bodies 
in quantities equal to their capacity or attraction for it, such bodies 
are said to be in their natural condition. When the natural 
quantity of electricity in a substance is increased or diminished, 
excitation takes place, and the substance is said to be electrified 
positively when possessing more than its natural quantity, and 
negatively when possessing less. 

The dynamic theory assumes that, from its creation, the earth 
has always possessed, and still possesses, a given amount of force 
or energy : That like the quantity of matter, it has never been 
increased or diminished: That heat, light, and electricity are all 
but different manifestations of the same force, and each is con- 
vertible into the other : That heat is produced by setting the mole- 
cules, or small particles of matter, in rapid vibration, which vibra- 
tions, striking the body, produce the sensation we call warmth 
(all have noticed the vibrations or waves of air proceeding from a 
hot stove or a tin roof on a hot summer's day) : That light is but 



16 ELECTRICITY 

the effect produced by the vibrations of ether, which strike the eye : 
That electricity, like heat and light, which were once thought to be 
exceedingly subtle forms of matter, is but a mode of force, which 
sets the molecules of ordinary matter in vibration and polarizes, 
or turns them in a certain direction. This theory has superseded 
the fluid theory and is now accepted by the scientific world as 
being correct. We know that electricity will produce both heat 
and light, and that heat in turn will produce electricity. Since 
the advancement of this theory the development of the science 
has been very rapid. 

In passing, it is but just to say that though the theory of 
Franklin has been exploded, yet he was the first to reduce elec- 
tricity to order, and his experiments and memoirs on electricity 
and other physical subjects gained him admission to the highest 
scientific societies in Europe, and have given him a permanent 
place in scientific history. 

A short and intelligent account of the nature of this wonderful 
force having been given two general rules or principles will now 
be stated, which the reader must remember in order that he may 
understand the processes and appliances hereafter described. 

The first principle is that bodies possessing like electricities 
will repel each other ; bat those possessing opposite electricities 
will attract each other. 



IN COMMON WORDS. 17 

In other words two bodies charged with positive electricity, 
or two bodies charged with negative electricity, will repel each 
other ; but when one is charged with negative and the other with 
positive electricity they will attract each other. 

This may be illustrated by rubbing a glass tube with silk and 
holding it near two pith balls suspended by silk cords. They 
will immediately fly to it and become charged with the same kind 
of electricity ; upon withdrawing the tube, instead of hanging near 
each other, as before, they will fly apart and remain in that position 
until they gradually lose their electricity. 

The second principle is that a current is produced when there 
is a suitable medium or conductor between the positive a?id nega- 
tive electricity, because of their strong affinity for each other. 

The subject will be further treated under the heads of Fric- 
tional Electricity, Voltaic Electricity, and Magnetism. 



ELECTRICITY 



Frictional Electricity. 

One of the commonest sources of electrical excitement is 
friction. As the reader has doubtless observed, frictional electricity 
first attracted attention. In horse's hair and cat's fur it is usually 
very abundant, and is frequently seen in frosty weather while 
grooming horses in a dark stable, or stroking violently the fur of 
a cat. 

It is, also, sometimes manifested by the cracking sound pro- 
duced by passing a gutta-percha comb through the hair when 
it is free from dampness ; also by the rising of the hair. It is 
often produced in great abundance in factories by the friction ot 
the bands on the wheels, and sometimes a spark two or three feet 
in length may be seen. 

When we rub two bodies together, the rubber and the rubbed 
body always assume opposite states, both positive and negative 
electricity, the reader will remember, being produced at the same 
time. 

In performing experiments in frictional electricity, glass is 
generally used to produce it, as it is very cheap, easily obtained, 



IN COMMON WORDS. 19 

and serves the purpose quite as well as other substances. 




PLATE MACHINE. 

For this purpose the plate machine is used and may be de- 



20 ELECTRICITY 

scribed as follows : A circular plate of glass is fixed upon an axis, 
and made to revolve between two leather pads covered with a 
mixture of tin, mercury, and zinc. 

The pads, rubbing against the plate, produce the electricity, 
which is conducted from the machine in various ways for perform- 
ing experiments. 

If, while the machine is in operation, the knuckle be placed 
near the conductor (which becomes charged with electricity from 
the revolving plate, and the view here presented gives a good idea 
of the plate machine), a spark attended by a sharp crackling 
sound will dar.t to the hand, producing a stinging sensation. 

Dr. Wall was the first to notice the electric spark. It is 
caused by the electricity passing through the air, and is produced 
when the conductor and the electrified body are not too far apart. 

If a person stand on a stool having glass legs, which prevent the 
electricity from leaving the body, and take hold of a chain fastened 
to the conductor of the machine, sparks may be drawn from any 
exposed part of the body, by a second person bringing his finger 
near the one on the stool, when the machine is in operation. 
Du Fay and the Abbe Nollet were the first to discover this. It 
attracted great attention and became a kind of fashionable diver- 
sion at the time. V 

The idea of accumulating and retaining this force suggested 



IN COMMON WORDS. 21 

itself, and in 1745 and 1746 many attempts were made to confine 
it in glass vessels containing" water or mercury. It was then dis- 
covered for the first time that shocks could be received. But it 
was not until the invention of the Leyden jar (so called from its 
having been invented in Leyden, Holland), that electricity could 
be bottled up, so to speak, and kept for an indefinite length of time. 

The jar is made by covering an ordinary glass jar inside 
and outside with tin-foil to within a few inches of the top. A dry 
varnished cork is placed over the mouth of the jar, and through 
the cork is run a wire, which ends above the cork in a brass knob, 
and below it in a chain, which rests on the bottom of the jar, thus 
coming in contact with the tin-foil. If a glass tube be rubbed 
with flannel or silk and repeatedly held near the knob of the jar, 
or the knob be held near the conductor of a plate machine, when 
it is working, the electricity will pass off in a succession of 
sparks and be collected on the inside and outside of the jar. 

The inside will be charged with positive, and the outside with 
negative, electricity, which the non-conducting glass between them 
prevents from uniting. But if one hand be put on the tin-foil on 
the outside of the jar, and the other on the knob, the circuit will 
be completed and a shock will be felt in the arms when the jar is 
small and in the chest when it is large. A number of these jars, 
having their knobs all united, may be made to form a battery, and 



22 ELECTRICITY 

may be charged with electricity or discharged in the same manner 
as a single jar. 

By means of this jar a shock has been given to as many as 
12,000 persons at the same time by their joining hands and the 
persons at the ends of the line touching, one the knob and the 
other the outside of the jar. 

The analogy between lightning and electricity seems first to 
have been noticed by the Abbe Nollet, but Benjamin Franklin 
was the first to prove that the electric spark and lightning are the 
same ; and that thunder and lightning aie caused by a discharge 
between two clouds charged with opposite electricities. 

In 1752, Franklin resolved to test the truth of his convictions 
by trying to gather electricity from the clouds during a thunder 
storm. He accordingly made arrangements for extending a wire 
to a great height from a steeple in course of erection in the city of 
Philadelphia. While waiting for the completion of the steeple, he 
one day noticed a boy's kite higher up in the air than he could 
possibly extend the wire, and the thought flashed upon him that he 
could perform the experiment by using the string as a conducting 
wire. The kite was covered with a silk handkerchief to prevent 
its being destroyed by the rain and wind. A sharp pointed wire 
was placed above it to collect the electricity. The loose fibres of 
the twine string were soon seen to stand out in all directions, and, 



IN COMMON WORDS. % 23 

putting his knuckle to the key fastened to the string, he drew off 
a spark. When the conducting power of the string was increased 
by its becoming wet, a Leyden jar was charged with which several 
experiments were performed. Thus it was established beyond a 
doubt that frictional electricity and atmospheric electricity are the 
same. This was regarded by scientists at the time as the greatest 
discovery of the age, and of itself was sufficient to immortalize the 
name of Franklin. 

Electricity is always present in the atmosphere in a greater 
or less degree, usually most abundant three or four hours after 
sunrise and sunset, and increases in quantity with the distance 
from the surface of the earth. Very little is known as to the cause 
of atmospheric electricity. Various causes have been assigned, 
among which may be mentioned the following : 

1. The friction produced by large bodies of rarefied air 
rubbing or chafing against denser or heavier bodies of air. 

2. To the condensation of vapors in the air, especially during 
a rain storm. 

3. To the chemical changes produced in the atmosphere by 
the growth of trees and plants. 

4. To the evaporation of the water of stagnant ponds and 
marshes, which contain a great quantity of decaying vegetable 
matter. 



24 ELECTRICITY 

As the conditions are not the same at all seasons of the year 
and in all places, so the amount of electricity in the atmosphere 
is greater in some places and during some seasons than at others. 
It is a noticeable fact that the loss of life and property caused by 
lightning is greater in rural districts and country towns and vil- 
lages than in large cities. 

Atmospheric electricity has its grandest manifestations in the 
vivid flashes and bolts of lightning which dart across the heavens 
and thrill us with their awful grandeur. 

The most destructive form of lightning is the forked, which 
takes a zigzag course because it travels so rapidly as to condense 
the atmosphere ahead of it ; and when it can find an easier path 
by darting to one side, it immediately does so, always taking the 
easier path. 

Sometimes atmospheric electricity exhibits itself in brilliant 
balls of fire at the yard arms and mast heads of vessels ; sometimes, 
in a brilliant light on the tops of masts and at the points of bayo- 
nets. Such manifestations are known as St. Elmo's Fire, and occur 
only when the air is surcharged with electricity. The Aurora 
Borealis, or Northern Lights, is also attributed to the electrical 
condition of the atmosphere. 

The velocity with which lightning travels is not known, but 
various experiments show that electricity travels from 11,000 to 



IN COMMON WORDS. 25 

288,000 miles per second, the rate depending upon the kind of 
conductor used and the intensity of the current. In other words, 
when a copper wire is used, it can be made to girdle the earth 
nearly twelve times in a second — a fact which is almost beyond 
the power of the imagination to conceive. Frictional electricity 
being more intense than voltaic of course travels faster. 

Conductors which are pointed have been found to be the 
best, and hence lightning-rods are always pointed and the points 
are covered with silver or platinum to keep them from rusting 
and thus losing a part of their conducting power. If the conduc- 
tor is good and of sufficient size, the electrical discharge takes 
place silently ; but if it is poor, the current, which cannot be hin- 
dered, will, if sufficient, destroy or demolish the conductor, as 
when lightning strikes a house or a tree. 

It is quite probable that a great deal of electricity is silently 
conducted by lightning-rods from the atmosphere to the earth. 
Death to persons and animals is due to the fact that their bodies 
offer sufficient resistance to the passage of the current to fatally 
paralyze the nervous system. 

Frictional electricity has no practical value as the largest 
plate machine is but one-tenth horse power. Its chief use is to 
illustrate the science in , colleges and schools, and particularly 
atmospheric electricity. 



26 



ELECTRICITY 



The following description, taken from The Electrical World, 
of the grave of the illustrious Franklin may be of interest to the 
reader : 

THE GRAVE OF FRANKLIN. 
About half a mile westward from the Delaware river, at Fifth and 
Arch streets, in the busiest part of Philadelphia, lie the mortal remains 
of that great philosopher and statesman, Benjamin Franklin. Like 

many others of those intra- 
mural cemeteries so fre- 
quently met with in Phila- 
delphia, Christ's Church 
graveyard is now hemmed 
in on every side by factories 
and stores. It is surrounded 
by a high brick wall, fast 
decaying from the storms of 
nearly two centuries ; and 
were it not that a breach, 
probably ten feet wide, was torn out in 1858 and an iron railing substi- 
tuted near Franklin's grave, the casual passer-by would not know that 
he was in the neighborhood of a cemetery. 

Upon entering the yard the visitor finds himself in groves of elm 
and chestnut trees, with tombs on every side of him. There is little 
sign of care-taking. Some of the tombstones are broken ; from others, 
still standing, the inscriptions have been worn away by the elements, 




IN COMMON WORDS. 27 

while others have fallen and lie covered with moss and hidden in the 
underbrush. But the visitor has left behind him the noise and bustle of the 
street, and he is soon beside the grave of the immortal "Poor Richard." 
This interesting spot is at the corner of the yard, as shown in the 
engraving, where Fifth intersects Arch street. The grave is covered by 
a slab lying on the turf, and bearing the simple inscription : 

Be a i nd lin l Franklin > 
Deborah,} x 79°- 

A stately elm tree, not shown in the engraving, springs directly from 
the foot of the tombstone, so closely that its roots must by this time 
have extended through the grave, and spreads its branches over the 
neighboring street. A broken flower-pot with a faded flower rests on 
the slab, and all else is left to the imagination of the pilgrim. 

At the head of the grave are two small upright stones, one to the 
memory of John Read, the father of Mrs. Franklin, and the other to 
"Francis F., son of Benjamin and Deborah Franklin, deceased Nov. 21, 
1786, aged 4 years, 1 month and 4 days." Next to the Franklin grave, 
to the southward, is a similar stone, inscribed simply : 

Richard 1 ^ , 

and Ba Q che > 

Sarah J l8 "' 

the daughter and son-in-law of Franklin. Some years ago, in excavat- 
ing a part of the yard, a tombstone was discovered which bore the name 
of Dennis Franklin, a child of the great philosopher, who died at an 
early age. 

It first occurs to the pilgrim that this perfect model of a hard-headed, 



28 ELECTRICITY 

intensely practical American should have a monument more expressive 

of his grand political, literary and scientific record ; but a little reflection 

shows that the plain stone and that quiet nook under the elm reflect 

the character of Franklin better than could a glowing epitaph. It was 

his wish, expressed in his will, to be buried "with as little expense or 

ceremony as may be," by the side of his wife, who was buried here 

Dec. 22, 1774 ; that " a marble stone, to be made by Chambers, six feet 

long, four feet wide, with only a small moulding round the upper edge, 

and this inscription : 

Be^aminl n> 

Deborah j I7 *~ 
be placed over us both." 

It will thus be seen that he fully expected to die in the decade between 
1780 and 1790, yet he survived the companion of his joys and troubles 
sixteen years, and did not join her in their silent resting-place until 
April 18, 1790. 

It may be worth while also to refer, as a contrast, to the epitaph which 
Franklin wrote for himself in 1728, when he was but 23 years of age : 

The Body 

of 

Benjamin Franklin, 

Printer, 

(Like the cover of an old book, 

Its contents torn out 

And stript of its lettering and gilding,) 

Lies here, food for worms. 

But the work shall not be lost, 



IN COMMON WORDS. 29 

For it will (as he believed) appear once more 

In a new and more elegant edition, 

Revised and corrected 

by 

The Author.. 

But his later life has taught us that imperishable fame does not rest 
upon the successful manoeuvres of a victorious army, and that Peace 
hath her victories no less than War. Muffled bells were tolled and 
minute guns boomed, while twenty thousand people followed this plain 
man to this grave. The nation's — the world's — sorrow was best exem- 
plified by the great Mirabeau, who, in announcing the death of Franklin 
to the French Assembly, spoke of him as ' ' the Sage whom two worlds 
claim ; the man whom the history of Empires and the history of Science 
alike contend for. * * * * * 



3o ELECTRICITY 



Galvanic Electricity. 



Galvanic electricity takes it name from Galvani, a professor 
of anatomy in the University of Bologna, Italy. 

About the year 1789, he accidentally discovered that bringing 
the legs of a frog, which he had recently killed, in contact with 
copper and iron produced convulsive motions in the limbs. He 
supposed this peculiar force to depend upon the nerves and mus- 
cles for its action; but Volta, of Pavia, in the year 1800, went a 
step further and showed that the action was due to bringing the 
two metals into chemical contact. 

On this theory he constructed his celebrated "pile," which 
consisted ot a number ol plates of copper and zinc, having cloths 
saturated with a weak acid placed between them, first a plate of 
copper, then one of zinc, and so on until the pile was completed. 
The whole was placed on glass (it being a non-conductor) and a 
wire attached to each end. The wire fastened to the zinc plate at 
the top of the pile was found to yield positive, and the one united 
to the copper plate at the base negative, electricity. A bright 
spark was produced by bringing together or separating the ends 



IN COMMON WORDS. > 31 

of these wires. Shocks could also be received, slighter than those 
from the Leyden jar, their force depending upon the number of 
plates. When a short piece of platinum was attached to the ends 
of these two wires, thus uniting them, it was heated red hot (the 
platinum being a poor conductor). 

The pile may be shown on a small scale by putting a piece of 
zinc under, and a piece of silver on, the tongue, and allowing the 
two to come in contact. As soon as they touch, the circuit is 
formed (the chemical action being caused by the saliva), and a 
peculiar sensation is felt in the tongue, accompanied by an 
unpleasant taste. If the eyes are closed, a faint flash is seen. 

Volta's was a very important as well as useful discovery, and 
has led to the construction of numerous batteries, all based upon 
the principle of chemical action as a generator of electrical force, 
and differing only in the amount of force produced and the cost ol 
production. 

A brief description of one of these batteries will illustrate the 
principle upon which they all operate. For illustration, Smee's, 
being a simple battery, will now be described. 

Three metallic plates are suspended from a wooden frame 
and kept separate from each other. The middle plate is of silver 
and coated with platinum. The two outside ones are zinc coated 
with mercury. The whole are placed in a glass or earthen jar, 



32 ELECTRICITY 

containing dilute sulphuric acid. As soon as communication is 
•established between the metals, a bubbling commences in the 
liquid, and voltaic electricity is produced. 

It may be interesting to the reader to know the theory of the 
action of the galvanic, or voltaic, battery. The most generally 
accepted theory may be briefly stated thus : 

Water is composed of two elements, oxygen and hydrogen ; 
and when connection is formed between the copper and zinc plates 
by means of water containing acid, the water is separated into 
these two elements. The zinc having a strong affinity lor oxygen, 
attracts it and forms oxide of zinc. The hydrogen, being set free, 
collects and forms small bubbles around the copper plate. This 
action causes the zinc to lose its positive, and retain its negative, 
electricity. The copper attracts the positive electricity, and thus 
a current may be formed between the zinc and copper plates, 
opposite electricities always attracting each other. To produce a 
current, it is only necessary to fasten one wire to the copper plate 
and another to the zinc plate and close the circuit by allowing the 
ends of the wires to touch each other. These ends are called the 
" poles " of the battery — positive and negative. 

The use of the acid in the water is to dissolve the oxide oi 
zinc, which forms on the zinc plate, and so keep a fresh surface of 
the metal constantly exposed. This is why a galvanic battery is 



IN COMMON WORDS. 



33 



constant in its action, so long as it is kept supplied with plates 
and acidulated water. 

Chemical action is supposed to be always accompanied by 
the development of electricity, though in its effects it may be so 

slight as to be imperceptible. 

The Callaud is the most 
complete form of Voltaic bat- 
tery, which has been adopted 
for general telegraphic purposes 
in the United States, and is 
called after the name of the 
designer of this type. 

For a clear description of its 
parts access may be had through 
the system here presented of 
numbering its parts. 

CALLAUD BATTERY. 

Names of Parts, 
i Battery Copper Connector. 5 Battery Zinc. 

2 Battery Zinc Connector. 6 Battery Metallic Copper pole 

3 Syringe hole cover and Sulphate of Copper. 

4 Wooden cover. Jar 6x8 inches. 

This form of battery requires very little care. 




34 ELECTRICITY 

Galvanic electricity differs from frictional electricity in being 
greater in quantity, but weaker in intensity. Frictional electricity 
is convulsive, sudden, and noisy; galvanic is powerful, constant, 
and silent. The lightning will dart through miles of intervening 
atmosphere, but a break in the circuit suspends all electrical action 
of the battery. It would encircle the earth rather than bridge a 
disconnection though but the fraction of an inch. An ordinary 
galvanic battery will produce the same chemical effects that could 
be produced by a flash of lightning. 

This last fact has led to the processes of electrotyping and 
electro-plating, which will be hereafter described. The differences 
pointed out will explain why galvanic electricity can be success- 
fully employed in connection with the telegraph and the telephone, 
and frictional cannot. 

Furthermore, galvanic electricity may be constantly gene- 
rated by the battery and always ready for use, without the aid of 
any machinery, which is necessary to develop frictional electricity 
in quantities sufficient for practical purposes. It is therefore 
cheaper. 

Because of its peculiar action on the nerves and the muscles, 
galvanic electricity is often applied to stimulate and restore them 
to activity in cases of paralysis and in acute forms of rheumatism. 
It has thus become a very valuable adjunct to the science of 



IN COMMON WORDS. 35 

medicine. It is also applied to the body in the form of an electric 
hairbrush, and by means of electric dumb-bells. 

Under this division of the subject will be described Electro- 
typing, Electro-plating, the Electric Fuse, and Electric Bells, as 
they more properly belong to it than to any other branch of elec- 
tricity. 



Electro-typing. 



The chemical effects and decomposing power of the galvanic 
battery are finely illustrated in the processes of electro -typing and 
electro-plating. 

Electro-typing was invented in 1837, by Professor Jacobi, ol 
St. Petersburg, and is done in various ways, one of which is the 
following : 

Wax is spread over a page of the type and an exact impres- 
sion is made upon the wax by strong pressure. Then the wax 



36 ELECTRICITY 

mold is removed and the face of it is given a metallic surface by 
covering it with pulverized plumbago (lead used for pencils). 
This is done to make the metal, deposited upon it, adhere to it. 

A solution of sulphate of copper, which is composed of 
sulphuric acid and copper, is put in a trough or vessel. Both the 
mold and the copper plate are submerged in this solution, the 
mold being placed at the negative, and the copper plate at the 
positive, pole of the battery. 

As soon as the battery commences to operate, the sulphuric 
acid and copper in solution are separated, the copper being drawn 
to the negative pole and deposited upon the mold, while the 
sulphuric acid goes to the copper plate, and combining with it 
furnishes a fresh supply of the solution. 

In this way the action goes on until a film of sufficient thick- 
ness is deposited upon the mold. When the film or shell has 
become as- thick as a sheet of heavy writing paper, the mold is 
taken out of the solution and the shell is taken off. 

It is then coaled with tin, because type metal, with which it is 
backed up, will not adhere well to copper. 

The shell is next placed on a plate, face downward, and sus- 
pended over a bath of melted type-metal. When it has become 
as hot as necessary, the molten metal is dipped up and poured 
over the back of the shell. The plate is then allowed to cool and 



IN COMMON WORDS. 37 

is made of a uniform thickness by means of a planing machine. 
When used for printing it is placed in a wooden frame. 

Plates can be made of type-metal, but copper is preferred, ii 
the book is likely to have a large circulation, as it is harder and 
more durable. 

The invention of this process has very greatly reduced the 
cost ol books, as the type need be set up but once; and after the 
plates are made, it may be broken up and distributed for use again. 
Furthermore, other editions of the book can be gotten out sooner 
than the first, because the delay of setting up the type is avoided. 



Electro-plating and Gilding. 

This process dates back to an earlier period than electro- 
typing. 

It was shown by Mr, Wollaston, in 1 801, that a silver coin 
could be covered with copper by means of the galvanic battery. 
The coin was burnished to prove that the plating was durable. 

It was not, however, until 1838, that this process was turned 
to practical account. Since then it has grown in importance, and 



38 



ELECTRICITY 



is now used in plating table ware, jewelry, gilding lamp-posts, 
monuments and various other things. 

Silver-plating is done in the following manner : 
A chemical solution of silver is placed in a glass or trough. 
Into this solution are placed a piece of silver and the article to be 
plated, the silver being attached to the positive pole and the 
article to the negative pole of the battery, as may be seen by 
the following cuts : 



^,-TTTTiiffiTirTi^Til'mTTmw 


\ l\A . 


~P^ "r^Z 




* A* 


\ 


,w--t-< 


TT^-' 


a - 


\A 


*? ^f^ir^^ 


lli 


fl 












11 


1 



When the battery is put in operation, the silver in solution is 
carried by the current to the negative pole and deposited upon the 
article, giving it a dead or frosted appearance. 

If, however, it is desired to polish the article, a few drops of 
bi-sulphide of carbon are put in the bath and have the effect of 
giving the plating a lustre. 

It is necessary to have the articles perfectly clean to give them 
a durable coating. This is accomplished by first putting them in 



IN COMMON WORDS. 39 

a boiling solution of potash to remove all grease from them. 
They are next dipped into a weak solution of nitric acid to remove 
any canker that may be on them, after which they are washed 
thoroughly. 

A single, double, or triple plate is formed according to the 
length of time the operation goes on. From three to six hours 
is the usual time required to give a good plating. 

One-half ounce of silver to the square foot makes an excel- 
lent plate. 

After the desired plate is given to the article, it is brushed 
well with a fine brass wire brush, which is revolved by a lathe. 
Finally, it is cleaned with fine Calais sand and polished. 

Gilding is done in much the same way, the principle being 
the same. 



Electric Fuse. 

An important application of electricity is exhibited in the 
electric fuse, which is used to explode the charges of powder or 
other material used in blasting, and torpedoes submerged under 
the water for the purpose of blowing up ships. 



40 ELECTRICITY 

By means of this fuse blasting has been made safe, as the 
charge may be ignited and the rock blasted when the workmen 
have gone a mile or so away. 

Some will doubtless remember that the famous explosion 
of Hell Gate, on the East river, was accomplished by a little girl's 
touching a porcelain knob and thus completing the circuit, and so 
causing the current to flow to the igniting point, and instantly the 
rocks, which had for all time past made the entrance from the 
ocean via Long Island Sound into the port of New York a 
perilous passage, were riven asunder and made easily removable. 

The electric fuse is constructed in different ways, the principle 
in all cases being the same, viz : that of passing a current of elec- 
tricity through a chemical mixture or a fine platinum wire, which, 
being a poor conductor, is heated and ignites the fulminate or 
charge through which it passes. 

The more resistance a body offers the hotter it becomes, so 
that even platinum, which is very hard to melt, has been fused. 
This principle will be more fully explained in the description of 
the electric light. 

Torpedoes are so arranged that the operator may complete 
the circuit and explode them at will, or the circuit may be com- 
pleted by the vessel's coming in contact with a submerged wire. 



IN COMMON WORDS. 



4i 



Electric Bells. 



Electric bells are used for many 
purposes where quick and audible 
signals are required for calling atten- 
tion, and are constructed of an electro- 
wound spools. magnet, or pair of wound spools, and 

a clapper, which being hung near the ends of the spools is acted 
upon by the electric current and drawn to strike the gong, which 
with the other parts is fastened to a base. 





ELECTRIC BELL. 

In a vibrating bell a sprirjg is fastened to the armature or 
clapper parts in such a way as to cause the interruption of the 




42 ELECTRICITY 

circuit every time the clapper moves and strikes the gong and is so 

returned, the result being a trembling ring as long as the push 

button is pressed. 

Any combination of signals may be 

arranged, and the same bell answer to 
call the "man-servant, maid-servant'' or 
"stranger that is within thy gates," or 
to call you when the "stranger" has 
entered your dwelling uninvited and for robbery or possibly worse 
purposes. 

In burglar alarms small contact points are caused to be 
touched by raising the windows, opening ttte doors, or stepping 
upon rugs designed for the purpose, or by cutting into your silver 
chest which in its every part — panel and post — contains a double 
thickness of metal, insulated from each other and making up the 
electric circuit, and must, by its design, be caused to touch in 
case of being punctured and so cause the alarm bell to be 
rung. 

The best form of burglar alarm equipment includes an annun- 
ciator which is made up of a set of magnets, one for each room or 
department of your house, or premises, and so connected by wires 
carefully concealed ; the action being, that if a door or window is 
opened a current of electricity is made to flow through the mag- 



IN COMMON WORDS. 43 

net for that room, a little leaf falls down showing the name of the 
room and the bell rings, and without delay the warning is given 
and advantages over the intruder presented. 

In 1 ail way signaling and telephoning, bells are rung over cir- 
cuits of many miles in length. 



Magnetism. 



The discovery of the magnet dates back to the time of Thales, 
a Greek, who discoursed upon it 640 B. C. Reference is also 
made to it in the writings of Homer, Aristotle, and Pliny. " The 
magnet-stone" says Pliny, "is found in Cantabria." 

Five hundred years before the Christian era, it was supposed 
that gout in the hands and feet and convulsions could be cured 
by the patient's holding a loadstone in the hand. In the fifteenth 
century it was employed as a cure for toothache, and a little later 
its beneficial effects were secured in the shape of magnetic tooth- 
picks. 



44 



ELECTRICITY 



Only natural magnets, or loadstones, were known to the 
ancients, and with these they magnetized needles, which they used 
in making compasses. 

It was not discovered until the year 1820, that artificial mag- 
nets could be made by passing an electric current through a bar 
of iron or steel. Magnets made in this way are called electro- 
magnets. This was a very important discovery as will be here- 
after shown. 

The power of loadstones is almost incredible. Sir Isaac 
Newton wore one in his ring. It weighed only three grains but 
would lift 746 grains, or nearly 250 times its own weight. The cut 
shows a horse-shoe magnet holding weight at its extremities. 

There are numerous kinds of artificial magnets, 
which take their names from their shape, as 
bar-magnets, horse-shoe-magnets, and magnetic 
needles. 

Steel and cobalt are found to be best suited for 
making permanent magnets, because being hard 
they retain the magnetism. Soft iron and nickel 
may be used to make temporary ones, because 
these metals soon lose their magnetism. 

The attractive force of the magnet is not dis- 
tributed equally through it, but is found to be 




HORSE-SHOE 
MAGNET. 



IN COMMON WORDS. 



45 



greatest at the poles or ends. If, however, a magnet be broken 
into any number of pieces, each piece will become possessed of 
a negative and a positive pole. In the centre it has no attractive 
power whatever. 

A thin intervening substance does not interfere with the 
attractive power of the magnet. This may be shown by scattering 
steel filings on a sheet of paper, and placing it above the magnet. 
The filings will collect around the poles in groups, as will be 
understood from the following two cuts. 

The general law of mag- 
nets is the same as that of 
electrical attraction and 
repulsion, viz : that like 
poles repel each other and 
unlike attract. 

The theory of magnet- 
ism is the same as that of 
electricity previously stat- 
ed, viz . a mode of force 
magnet with filings. which polarizes, or turns, 

all the molecules in a certain direction. Hence the magnet is but 
another form of electrical force. 




4 6 



ELECTRICITY 



All the extensive practi- 
cal and useful applications 
of electricity have been 
made by means of the 
magnet. Under this divis- 
ion of the subject, the 
Compass, the Telegraph, 
the Telegraph Cable, the 
Telephone, the Electric 
Light, and the Electro- 
motor will be described, 
as they all embrace the 
magnet in some form. 




MAGNET WITH FILINGS. 



IN COMMON WORDS. . 47 



The Compass. 



If the magnetic needle be suspended or poised so as to move 
freely, it will always point north and south, or nearly so. The 
same end invariably points north, leaving the other end pointing 
south. 

This can only be explained by considering the earth a great 
magnet, having its south magnetic force concentrated in the 
Northern Hemisphere. Hence the north pole of the needle points 
in that direction, and the south pole of the needle points towards 
the north pole of the earth, which is the Southern Hemisphere, 
because opposite poles of the magnet attract, and like poles repel, 
each other. 

Whether we call a certain end of the needle the north pole, 
or the south pole is only a matter of custom, as we could consider 
the north pole of the earth to be in the Northern Hemisphere, 
and the end of the needle which points in that direction the south 
pole of the needle. 

The fact that the magnetic needle invariably points in the 
same direction seems to have been discovered at a very early date, 
and led to the invention of the mariner's compass, which is 



48 ELECTRICITY 

supposed to have had its origin in China. It was successively 
introduced into India, Arabia, and Europe. 

If the Chinese annals are to be credited, it was known to that 
people and used by them nearly 3000 years ago ; but it probably 
consisted of nothing more than a piece of loadstone fixed on a 
cork and placed on smooth water. 

The mariner's compass now used may be described as fol- 
lows : 

« 

A needle is magnetized and placed upon the point of a short 
pivot or post. A round card, having the cardinal points and 
smaller divisions marked upon it, is attached to the needle in such 
a manner that both the card and the needle may freely float around 
according to its magnetic impulse. The number of points on the 
card is thirty-two, and they are subdivided into half and quarter 
points. 

Reading these points is termed boxing the compass. The 
needle and card are enclosed in a brass case, as brass has no 
attraction for the needle and will not affect or influence its direction. 

The box containing the compass is hung on gimbals in the 
binnacle, so that it will always be in a horizontal position, no 
matter how much the vessel may pitch and roll. Thus the face 
of the compass is always turned upward and the course of the 
ship may be easily ascertained. 



IN COMMON WORDS. 49 

The surveyor's compass and all kinds used on land have the 
needle placed above the card. 

That a compass may be good, it is necessary that it should be 
steady, active, and easily influenced; and that it should be made 
so that it may be easily corrected, when it has deviated by local 
attraction. 

The invention of this instrument has made it possible to tra- 
verse the oceans and seas with almost unerring certainty, and has 
converted them into great highways over which the commerce of 
the world is carried. 



The Telegraph. 



Various means have been employed to transmit messages 
between distant points, but only four of the different systems based 
on the action of the galvanic battery will be described, viz : 
Sommering's, Morse's, Bain's, and House's systems. 

An endeavor was made to use frictional electricity for the 
transmission of messages, but it was not until after the discovery 
and the various improvements of the galvanic battery, that a con- 
tinuously working instrument could be produced. 



5 o ELECTRICITY 

\ 

The present system of telegraphy owes its existence to the 
fact that a current of electricity passed through a bar of iron will 
magnetize it. The use of the magnet will be fully explained in the 
description of the Morse system. 

Sommering's system of telegraphing, invented in 1808, was 
not based upon the action of the magnet, but upon the decompo- 
sition of water by galvanic electricity. It consisted of as many 
wires as there are figures and letters in the alphabet. In other 
words, it had thirty-six wires. Each wire was put in a tube con- 
taining water, and each of the thirty-six tubes had either a figure 
or a letter placed upon it. The current from the battery was 
passed through the wires representing the letters in a word or the 
figures composing a number. The word was spelled out or the 
number was ascertained by noticing the bubbles in the tube where 
the message was received. 

This, of course, was a very expensive and cumbersome appara- 
tus ; and as messages could not be sent rapidly, it was of no 
practical value. 

Samuel F. B. Morse was the first to invent a practical system 
of telegraphy, and to make it one of the greatest agencies in the 
advancement of civilization and prosperity. 

In 1832, while on his way from Europe to America, he 
invented his system; and in 1835 he constructed a short line, 



IN COMMON WORDS. 51 

but his first patent was not granted until June 20th, 1840. 

As early as 1837, he applied to Congress for aid, but was 
refused. Many persons, among whom was Webster, believed him 
to be crazy. At last Congress, in 1843, to make the experiment, 
appropriated the sum of $30,000 ; and a line was constructed 
between Baltimore and Washington. 

On May 27th, 1844, the nomination of James K. Polk, by the 
democratic convention, then in session in the city of Baltimore, 
was transmitted over the wire to Washington. That message 
immortalized the name of Morse ; and succeeding generations will 
continue to regard him as one of the greatest benefactors of his 
race. 

Several discoveries necessarily preceded Morse's invention. 

In 1825, Mr. Sturgeon, of London, discovered that a coil of 
wire wrapped around a bar of soft iron will give it the properties 
of a magnet, so long as the current of electricity is passing through 
the wire. 

The current produced by the galvanic battery was found to 
be too weak to overcome the resistance of a long transmitting 
wire. This was a serious practical difficulty, and was conquered 
by Prof. Joseph Henry of the Smithsonian Institute, at Washington. 

In 1 83 1, he invented the kind of magnet used in the Morse 
system. 



52 



ELECTRICITY 



He, also, discovered a means of combining circuits, consti- 
tuting the important invention of receiving magnet, and the relay 




ORIGINAL MORSE MACHINE. 

or local battery, as they are now familiarly called. By this com- 
bination, a weak or exhausted current can call to its aid, or sub- 
stitute for itself, a fresh and powerful one. 



IN COMMON WORDS. 53 

Morse's invention may be described as follows : 

By means of a galvanic battery a current of electricity is sent 
over the wire which was by a system made and broken so as to 
move a pencil upon a moving- paper ; the plan of his instrument 
was necessarily crude, a view of it being given on the opposite 
page. 

He procured from a blacksmith a horse-shoe shaped piece 
of iron, around which he wound by hand some copper wire, which 
he had covered also by hand with cotton thread, thus making 
his magnet, which he fastened upon a large wooden frame and 
connected his line wires to it ; his pencil holder, which also car- 
ried the armature which was moved by the electric action of the 
magnet, was probably two feet long, made of two wooden strips ; 
the paper ribbon upon which the little characters were scratched 
was propelled by wooden clock works. 

Evolution in this line has at this day produced a much more 
complete instrument for the telegraph. The view given on the 
next page shows the "Relay," " Sounder," and " Key" upon one 
base. 

The first being connected to the line and the delicate instru- 
ment which receives the impulses from the line, and being a quiet 
instrument it is made to transfer the signals by the movements of its 
lever (" armature"; to a louder instrument — the sounder, which be- 



54 



ELECTRICITY 



ing fed by a battery 
in each office where 
it is, speaks out 
loud, and trained 
operators read the 
message by the 
hammering of its 
lever upon the 
screws ; the trained 
ear quickly meas- 
ures the length of 
time it requires to 
make what on the 
paper in the older 
telegraph instru- 
ment would be a 
M dot" and its differ- 
ence as compared 
with the •'dash, 1 ' 
and the alphabet is 
made up of the com- 
bination of dots 
and dashes. 




IN COMMON WORDS. 55 

The " key 1 ' is the signal or letter sender, it, being connected 
in the line, breaks the current in all the instruments on the line as 
its lever is raised., and makes it again as it is pressed down, the 
letters, therefore, being made up of makes and breaks. 

The alphabet made up by Prof. Morse, strange to say, remains 
in force to this day, and is almost universally used by operators 
who use the recorders and paper, and the ''sound readers" as well, 
and is as follows : 

THE MORSE TELEGRAPH ALPHABET. 
A B C D E F G 



J*. A _.£_. __?«, L - 


M_ _N_ 


-°L .,.?.. .5L. m ^ m .?- JL 


_U_ 


V W X Y z 


& 


Numerals. 




12 3 4 


5 


6 7 8 9 





Punctuation. 




Period. Oomma; Semi-colon. Quotation. 


Exclamations Interrogation; Parenthesis. 


Paragraph; 



To those who are interested in the manner of electrically 
connecting up telegraph machinery, the following picture may be 
of interest and service to them. 




Bain's system was in- 
vented in 1845. LikeSom- 
mering's,it did not require 
any magnet. His was an 
electro-chemical tele- 
graph, and transmitted 
messages by recording 
dots and dashes on chem- 
ically prepared paper, 
placed on a revolving 
metallic plate. Over this 
plate was a stylus or sharp 
pointed instrument, which 
made the dots and dashes 
on the paper directly un- 
der it. 

House, about 1845, a ^ so 
invented an instrument by 
which the letters of the 
Roman alphabet are print- 
ed on a strip of paper. It 
has a key-board similar to 

that of a type-writer, and 

(56) 



IN COMMON WORDS. 57 

by touching a key the corresponding letter is printed on a slip of 
paper at the other end. The message is thus printed in full and 
ready to send out by simply tearing off the strip. 

This system was at one time extensively used throughout the 
United States; but Morse's system with slight modifications is 
now employed throughout the civilized world. 

' In addition to a number of well used systems of Duplex — 
sending a message in one direction on a wire while another mes- 
sage is being sent in the opposite direction on the same wire, — 
and likewise a multiplication of this, as shown in the quadruplex, 
and sextiplex, which are becoming common, a system of multiplex 
has just been perfected and is now in operation between Boston 
and Providence, by which, it is claimed, seventy-two messages 
may be sent over the same wire at the same time, and in the same 
direction at the rate of three words per minute for each circuit; 
or thirty-six messages, if sent in opposite directions. 

The value of the telegraph to commerce, journalism, and 
science cannot be over-estimated, and can only be measured by 
imagining the evils which would follow the loss of it. 



58 ELECTRICITY 



Electric Wires. 

For telegraphic uses wires of a medium weight or thickness 
are used, while for telephoning finer wires answer, the difference 
being that the telephone uses feeble currents, the telegraph heaVy 
battery power; but for electric lighting the heaviest wire is 
required on account of the intensely heavy current necessary to 
be carried. 

With the vast increase of wires for all purposes, like 
great cobwebs, in our large cities, the apprehension is grow- 
ing that soon the light from heaven may be considerably dark- 
ened, to say nothing of the homeliness of the arrangement(P). 

The owners of wires are crying to the law makers and the 
executive departments of cities for further liberties and the people 
are arraying themselves against a continuance of the present priv- 
ileges. 

The electrically interested people are dreading the expense 
of putting the wires under ground and are fearful lest, in telephony 
especially, they may be defeated in transmission by the earth's inter- 
ference, for the earth is greedy to absorb all the electricity she can 
steal from the wires. 



IN COMMON WORDS. 59 

The undergrounding subject occupies the first position in 
the general public attention in the large cities to-day, and grave 
are the doubts about successful working for long periods, and cer- 
tain is the excessive cost of a wholesale removal from above sur- 
face to below it. 

Be the conduits designed as they may, the writer is doubly 
sure the most important requirement is good " insulation," which 
means the covering on the wires which keeps the electric current 
from escaping. 



Telegraph Ocean Cables. 



The first submarine telegraph cable was laid by Dr. O'Shaugh- 
nessy, in 1839, near Calcutta. The telegraph line was twenty-one 
miles long, seven thousand feet of the wire being submerged. 
The submerged wire was covered with cotton thread saturated 
with pitch and tar. 



60 ELECTRICITY 

In 1842, Prof. Morse is said to have laid a wire between New 
York and Governor's Island. These were different, however, in 
their construction from the cables which now span the oceans and 
seas, though the principle of sending messages is the same viz : 
that of telegraphing at a great distance. 

Our present system of laying cables in the open sea began by 
laying a submarine cable between Dover, England, and Cape 
Grinez, France. This cable was laid in 1850 and was twenty- 
seven miles long. 

It would be quite impossible in a book like this to even name 
all the cables that have since been laid. As near as the writers can 
ascertain there have been two hundred and four oceanic cables 
laid throughout the world (including the one recently laid), fifty- 
seven of which were not in operation in 1882. 

The writers, will, therefore, confine themselves to giving a short 
history of the Atlantic cables by which our own continent has 
been linked to Europe and through which we are daily made 
acquainted with the important events happening throughout the 
civilized world. 

In 1857, tne steamships " Niagara " and "Agamemnon" 
endeavored to lay a telegraph cable between the coast of New- 
foundland and Ireland, but without success. The next year they 
made a second attempt, which proved successful. The sixteenth 



IN COMMON WORDS. 61 

day of August, 1858, is memorable on account of a message and 
reply transmitted between Queen Victoria and President 
Buchanan. 

This' was the first time in the world's history that the iulers 
of two great nations had conversed across the ocean. During the 
first twenty -three days four hundred messages were sent. It then 
lost its conducting power and was abandoned. 

Inseparably connected with this transatlantic cable enterprise 
is the name of Cyrus W. Field, who by his perseverance and 
untiring energy, both in this country and in England, secured the 
necessary means for its accomplishment. 

In 1865 an attempt was made to lay a second cable, and the 
immense steamer " Great Eastern " was entrusted with the enter- 
prise. 

The work of laying the cable commenced on the 23d of 
July. After working for several days, during which a considera- 
ble portion of the cable was laid, it parted and the broken parts 
could not be found. This cable was even stronger than that oi 
1858. 

In 1866, this enterprise was undertaken a second time by the 
" Great Eastern/' and was entirely successful. She also grap- 
pled the end of the one laid the previous year, and spliced it : so 
that there were two lines of trans-atlantic telegraph. 



62 ELECTRICITY 

The length of the cable in each case is about sixteen hundred 
nautical miles. 

It was nowhere placed more than two and seven -tenth miles 
below the surface of the water. It was paid out at the rate of six 
miles per hour, and the length of the inclined plane between the 
bottom and the ship was seventeen miles. 

On the 16th of June, 1873, the "Great Eastern" assisted by 
three other steamships, each fitted out with all the necessary 
appliances for laying and picking up cable, began the work of 
laying the fifth Atlantic cable between the coast of Newfoundland 
and Ireland. During the first eleven days, the " Great Eastern " 
laid seventeen hundred miles of it. 

Siemens Brothers, near London, manufactured this cable. 

It consists of a thick central wire which runs through a pecu- 
liar composition. Eleven smaller wires are placed around it, the 
composition cementing the whole together. Then it is coated 
with gutta-percha, and served with manilla fibre until it is three- 
fourths of an inch in diameter. It is next covered with ten iron 
wires, each having been previously wrapped with hemp, and 
passed through two tanks of tar in order that it may be thoroughly 
coated. Then it is coiled away in large tanks, where it remains 
until used. 

By the above description, the reader has observed that the 



IN COMMON WORDS. 63 

cable consists of a wire for conducting the current of electricity 
and an insulating compound, to prevent the escape of the elec- 
tricity from the wires ; also sheathing and iron armor to protect 
against rubbing or other injury, and to increase its strength. 

It is necessary that the cable should be strong so that it will 
not easily break, that it should not be affected by the action of 
the salt water, and that the conducting wire should be insulated 
to prevent any of its electricity from being carried off by the 
water, which is a good conductor, and would carry the current 
to the ground and so cut it off, and destroy the cable's usefulness. 

What has been said concerning the usefulness of the tele- 
graph, may be more strongly affirmed of the cable. It has indeed 
linked the continents of the earth together and enabled us " to 
speak the world around." 

The present cost of sending a message from Philadelphia to 
Liverpool is fifty-three cents per word. 



64 ELECTRICITY 



The Telephone. 



" The telephone, which makes a whispering gallery of the 
round earth," is fast making a very interesting and important his- 
tory, and at this time while much attention is being drawn to it, 
diligent search is being made for the beginning and earliest hand 
in it; among the scraps comes to us quite a clear prophecy of it, 
dating to 1847, when in London a fairy tale was published in 
which the story ran : 

The little Bee informed the Queen that the " metallic 
threads " running through the air above would convey " any 
message you please." The Queen told the Bee what to say, and 
the " words went tearing through the atmosphere on the wings of 
the lightning messenger." 

The passage is accompanied by a snatch of poetry in which 
the whole telephonic idea is given : 

" Let their voices be heard 

At a distance no voice could reach ! 

And swiftly as thought 

Let the words be brought, 

And the lightning endowed with speech!" 

Leon Scott and Mr. Barlow were the first to invent electric 



IN COMMON WORDS. 65 

telephones, which recorded the vibrations on a travelling ribbon 
by means of a delicate marker. But the telephone did not become 
of practical or commercial value, until it was made to convey 
these vibrations directly to the ear. 

This is done by means of a u receiver," which contains a mag- 
net for reproducing the vibrations. 

In order to understand the telephone, it is necessary to know 
how sound is produced. 

Voice is produced by the action of the breath upon the cords 
in the throat. The cords being made to vibrate by expelling the 
air from the lungs, produce sound in the same manner as the 
string of a violin when the bow is drawn across it. 

This sound or voice is converted into words by means of the 
organs of speech viz : the teeth, tongue, lips, and palate. 

These modified vibrations leaving the mouth set the air in 
vibration. The vibrations, or waves of air, striking upon the ear, 
produce modified sounds or words. In other words, sound is 
nothing more than vibrations or waves of air falling upon the ear, 
which converts them in a mysterious way into sound. 

The different sounds depend upon the number of vibrations 
per second, the lowest number which will produce it being six- 
teen. 

To Reiss, of Germany, the credit is given of having first 



66 ELECTRICITY 

transmitted musical sounds through a telegraph wire by electrical 
means. 

He used a square wooden box, through a hole in the front ol 
which he inserted a speaking tube mouth piece, and over a hole 
in the top of the box he tightly stretched a membrane. 

Any sound produced in the box would set the air within in 
vibration, and cause the membrane to vibrate. To the centre of 
the membrane was fastened a piece of platinum and connected by 
wire to the other end of the line ; against this platinum a sus- 
pended piece of platinum rested. This was connected through a 
battery and the circuit made complete through the ground or by 
a return to the opposite end. 

As the membrane was moved it disturbed the electric circuit 
and this was sent to the other end and was correctly repeated. 
The receiver was made of an iron bar mounted on a sounding 
board. Around the rod was a coil of wire. 

A current on this line and through this wire magnetized the 
bar and caused vibrations and faithful rendering of the pitch of 
tones thrown into the transmitting box. 

Elisha Gray, of Chicago, in 1874, improved this by having a 
faithful reproduction in giving the variable intensity as well as the 
pitch of a sound. Afterwards he added quality to it, and as a 
result articulate speech was accomplished ; but to Prof. A. Graham 



IN COMMON WORDS. 67 

Bell, of Boston, the credit is generally accorded of accomplishing 
this in the most effective manner. 

Many, however, are the aspirants to-day to divide the great 
honors with him and much good coin has been and is at the 
present time passing to the treasury of the legal fraternity in the 
contest. 

Daniel Drawbaugh, of Pennsylvania, is the chief contestant, 
and claims priority. Unlike some of the other contestants, neither 
he nor his companies have done anything in creating and operating 
a system, and nothing comparatively is known as to the form of 
instruments they would use, but it is to be presumed that if success- 
ful in the present legal contest, they would build up a system from 
simple forms somewhat similar to the present Bell instruments. 

Many have been the contests between the company operating 
under the Bell patents and others who have, at least, made import- 
ant improvements upon the system, and a great many of these con- 
tests have resulted in a union of interests ; among the many workers 
whose improvements have been added to the Bell system are Dol- 
bear, Gray, Edison, Berliner, Blake, Irvin, Gower and Hunnings ; to 
give fully the work of each in this volume would be quite impossible. 

The Bell Telephone is shown on the following page in two 
views; one shows the external appearance, the other the parts 
which compose it. 



68 



ELECTRICITY 




IN COMMON WORDS. 69 

The cut shows so plainly the form, that description seems 
almost needless, though a brief explanation of the parts might be 
desired by some. 

An electro-magnet or spool of copper wire is fastened to the 
end of a steel bar which has been charged with magnetism ; the 
ends of the wire are carried down to the outer part of the rubber 
case, and connected by screws to the line wire. In front of the 
spool, and a little way from the end of the bar magnet, a piece of 
11 ferrotype" sheet iron is placed. 

When a current of electricity is sent into the telephone and 
through the spool of wire, the sheet iron plate is caused to vibrate 
in unison with the breaking of the current, by reason of the 
alternate attractions and cessations of attraction of the plate by 
the electro-magnet, and a sound is produced. 

An additional view is given of the operation of using the first 
Bell Telephones, in which a magnetic telephone was used for speak- 
ing, but as improvements in strength of " sending" or transmitting 
telephones were demanded, Dr. Blake, of Massachusetts, designed 
and invented the instrument now so generally used, called the Blake 
Transmitter, which is a square box with opening through the 
door; on the inside of the door an iron plate is loosely held, 
against the inside of which is hung and supported by a spring, a 
platinum bead ; beyond this is a carbon button suspended in the 



7o 



ELECTRICITY 



LINE 




THE FIRST BELL TELEPHONE. 



same way ; these 
two springs are in 
the circuit of a bat- 
tery, and as one 
speaks against the 
plate or "dia- 
phragm," the point 
of contact against 
the carbon button is 
displaced and 
changed, and varia- 
tions of intensity 
produced in the cur- 
rent. 

The adjustment of 
the springs is so 
nicely regulated, 
that the varying 
pressure between the 
contact points is 
carried to the Bell 



Telephone, which is the receiver at the other end of the line, and 
there faithfully interpreted. 



IN COMMON WORDS. 



7i 



For the purposes of signaling, a magnetic generator is used 
to ring bells. This generator is made of steel horse-shoe mag- 

Fig. I. 




GENERATOR, TELEPHONE, ETC. 

nets, with a revolving pair of spools of copper wire, with iron 
centres near the ends of the horse-shoe ; by turning a crank, the 



72 



ELECTRICITY 



spools are revolved, and so a current is sent which rings the 
bells. 




The cut on 
the preceding 
page shows 
the full Bell 
Telephone 
set, of the 
original 
"Bell" pat- 
tern, and, al- 
though old, 
shows dis- 
tinctly the 
separate in- 
struments 
making up 
the set for 
signaling, 
speaking, and 
hearing. 



IN COMMON WORDS. 73 

To the student or operator, the diagram given in the preceding 
page will be of value ; it shows the wire connection between the 
parts of the Bell Telephone standard equipment. 

Daniel Drawbaugh, of Eberly's Mills, Pa., claims that his first 
electrical transmission of articulate speech dates back as far as 
i860, and that such a way of talking by wire was a dozen years 
old when Mr. Bell announced his triumph. 

From an examination of the models exposed to public view 
for a few days after the opening of the Electrical Exhibition at 
Philadelphia (and then covered over, or removed, because the case 
was being adjudicated in the United States Circuit Court of New 
York), one would be led to suppose that Bell, Edison, Blake, and 
Righi had all been peeping through Mr. Drawbaugh's key- 
hole and stealing designs for their instruments and improve- 
ments. 

It does sometimes occur, however, that striking resemblances 
are brought out simultaneously by inventors far removed from 
each other. 

This brief dissertation on telephones would be incomplete 
were we to omit the Clay telephone, the one which has probably 
shown the most earnest purposes of competition with the com- 
panies operating under the Bell patents. 




CLAY TELEPHONE RECEIVER. 



IN COMMON WORDS. 75 

The cut on page 74 shows the Clay receiver, which is quite 
fully described by the picture. Its principal parts are a three 
pronged steel magnet wound with wire as shown, and with the 
usual plate of iron in front. The middle limb is one of polarity, say 
positive, and the two outside ones are of the opposite or negative. 

A virtue is claimed for the peculiar form of winding on the 
magnet, and that disturbing effects from other lines and cross- 
talk from other wires is obviated. 

In the Clay transmitter, the usual induction coil is used, as in 
the Blake transmitter, but the manner of doing so is very different. 
This coil's weight is used, by the peculiar hanging of it, to press 
a carbon pencil against the " speaking plate," which will be readily 
understood from the cut of transmitter, which gives a sectional 
view of the box. 

To cause transmissions the words are directed against the 
square panel above the shelf, which causes its vibration and 
consequently a series of changes in pressure on the carbon pencil 
inside, this is sent upon the wire and to the receiver at the opposite 
end of the line. 

The most recent aspirant, who claims priority of invention 
antedating all others by several years, is one Antonio Meucci. He 
is making some stir in the telephonic world, through what is 
claimed to be a strong combination of capital and experience. 



7 6 



ELECTRICITY 




Grountf. 



CLAY TRANSMITTER. 

This transmitter is inclosed in the signal box to be seen in 
the next cut, which shows the Clay complete set. 




CLAY COMPLETE SET. 



78 ELECTRICITY 



Electric Light. 



The electrrc light is produced by passing a current of 
electricity through a filament, or thread, of carbon, or between 
two sticks of carbon fixed at the positive and negative ends of the 
circuit. 

Voltaic electricity may be used, or electricity generated in 
magnets by magneto-electric or dynamo-electric machines. 

The latter source only is of any practical value for lighting 
streets or buildings, and will be fully described hereafter. 

The light emitted by fire-flies and glow-worms is attributed 
by some to electricity in the body, and the nervous action by 
which they flash is thought to be in the nature of voltaic impulses 
from the battery — the brain. However, this is only speculation. 

The attention of the public was first called to the electric 
light in the year 1846, by the patent of Greener and Staite. 

Their lamp consisted of an arrangement by which small pieces 
of pure carbon, inclosed in air-tight globes, were made brilliant 
by passing currents of galvanic electricity through them. 

To describe the lamp more fully, two small bits or sticks of 
pure carbon were fixed so that their points would nearly touch 
each other. In this position they were kept by means of clock- 



IN COMMON WORDS. 79 

work, which automatically adjusted them as they wore away, by 
slowly moving them towards each other. A current from the 
battery was transmitted through these sticks, but the circuit could 
not be completed without spanning the small space between the 
two points. The carbon being slightly separated and also a poor 
conductor, an intense heat at the points was produced, together 
with an intensely brilliant light. 

According to the dynamic theory, previously mentioned, the 
more resistance a body offers to a current of electricity the more 
rapidly its molecules are made to vibrate, and the hotter it becomes, 
as a matter of course. When the carbon is heated to a white 
heat, it makes a very brilliant light. 

Platinum cannot be used for lighting purposes, because it 
becomes so hot as to melt. 

The principle of the electric light, therefore, consists in pass- 
ing a strong current of electricity through a resisting body, which 
will neither melt nor be quickly consumed. 

The dynamo machine or generator of electricity, used for the 
production of the electric light and motive power, consists of an 
armature, or ring of soft iron (sometimes surrounded by a wire), 
which, by steam or other power, is made to revolve between the 
poles of a single magnet, or between two magnets ; which, in short, 
is a transformation of work into electricity ; and while this means 



So ELECTRICITY 

seems to be, and is complicated, it is the most economical where 

powerful currents are used. 

The horse-shoe magnet will serve to illustrate it. The ends 
of the shoe are called the poles — positive and negative. Between 
and around these poles is the "field'' of the magnet. If an 
armature be made to revolve rapidly in this field or between these 
poles, the magnet becomes strongly electrified at these points. 

Positive electricity having a strong affinity for negative, it is 
only necessary to produce a current to connect the two poles, or 
ends, of the magnet. 

To produce the electric light, attach a conducting wire to the 
negative pole of the magnet, and a stick of carbon to the other 
end of the wire. In like manner connect the positive pole of the 
magnet and bring the two sticks against each other, and let the 
electric current pass between them. As the connection so made 
is poor, heat is produced, and, the sticks of carbon being sepa- 
rated, the force of the current throws off from the surface and 
ends of the sticks, the carbon in small particles, heated up to a 
state of incandescence. 

Illumination is thus accomplished by this process of vapor- 
izing, transferring, and throwing off in great numbers, these parti- 
cles which form an arc of light between the ends of the two sticks 
of carbon ; hence the name of lamps in which carbon is con- 
sumed — " arc lights." 



IN COMMON WORDS. 



81 




ELECTRIC ARC. 



A view is here given of the appearance of the burning 
carbons in the arc lamp. 

This is an enlarged view of the arc lamp, in the box of which, 
above the globe, the mechanism and magnets are contained, for 
feeding and regulating the carbon sticks, which are seen within 




the globe. The upper stick 
is in the positive side of the 
current, and the lower one in 
the negative. In the first the 
consumption is about one inch 
per htmr, and half as much in 
the lower, so that it is necessary 
to visit the lamps every day 
and renew the carbons. 

Many of the lamps are made 
with double carbons for double 
length of service without atten- 
tion, and are used in winter, for 
all night work, etc. ; but during 
the actual burning of the lamps 
the devices, which differ in the 
different systems, so nicely con- 
trol the feeding that the con- 
sumption is regular. 

Carbons are generally made 
from the coke-like accumula- 
tion which fastens itself to the 



IN COMMON WORDS. 83 

inside or ceiling of gas holders. It is ground fine, mixed with 
some substance like molasses to hold it together, and baked hard. 

The sticks cost about three and a half 
cents each, twelve inches long, when 
bought in very large quantities. 

A contracted view is given of an arc 
lamp as it is prepared for street work, 
with hood for protection from the 
weather. We believe the system of 
street lighting was first introduced in 
this country in 1878 on Manhattan 
Beach. The growth since then of city 
illumination by lamps upon posts and 
upon high masts and towers, erected at 
street junctions, has become more or 
less extensive throughout the world. 

It will be remembered there are these 
lamp and hood. two general classes of electric lamps, 

one being that just named — the arc — in which carbon is con- 
sumed, and the other, the " incandescent," or that in which there 
is no consumption of carbon but a heating only, which is accom- 
plished by having the fine carbon filament kept in a vacuum or 
sealed globe, from which air is excluded. 




8 4 



ELECTRICITY 




WESTON INCANDESCENT LAMP. 



The incandescent 
lamp is usually made 
to give a less intense 
light than the arc 
lamp, and is best 
adapted to home and 
lightingsmall rooms, 
although latterly 
very large lamps of 
this class are being 
introduced for light- 
ing large spaces. 

The names arc 
and incandescent are 
misnomers to a cer- 
tain extent, for in the 
arc light the illu- 
mination is due to 
incandescence of the 
particles of carbon 
thrown off; and 
again, there is a form 
of lamp like that of 



IN COMMON WORDS, 85 

Varley's, Werderman's, Reynier's, &c, which is classed incan- 
descent and yet one piece of carbon — a pencil — is consumed 
where it presses against a block of carbon. This form is very 
little used, and probably not at all in the United States at this time. 

A view is here given on the opposite page of a Weston 
incandescent lamp of improved form of carbon. This is given 
as a type of the general form of incandescent lamps. 

The filament, or wick, of these lamps has generally been 
made of carbonized paper, silk or other thread, and fibre of 
bamboo wood as in the Edison lamp, while the one shown is made 
from a new substance named Tamadine, and in chemical compo- 
sition, much the same as paper or vegetable fibre, but without 
fibrous structure. 

In making this class of lamps nearly all the air is exhausted 
from the globe, before it is sealed up, by the use of mercury pumps. 

This is probably the future light for our homes, as from it no 
gases are given off to vitiate the air ; also very little heat. Another 
valuable consideration is its perfect safety from fire. The wish 
that its production and maintenance may soon be cheapened is 
becoming general. 

Within the past few days we have been admitted into the 
secrets of a new invention in incandescent lamps. If the expec- 
tations of the inventor, Mr. Beck, of Paris, are realized, a step in 



86 



ELECTRICITY 



advance will be taken and a valuable accession made to the com- 
fort and conveniences of rural homes, as well as to those located 
within reach of the central lighting systems of the large cities, 

where the electric power is 
distributed through mains 
to all subscribers on the 
way. 

The important feature 
of this invention is the 
making of an incandes- 
cent lamp which is run 
by a battery, and which can 
be carried about like a 
kerosene lamp. 

The globe is the peculiar 
part of the lamp and 
a description of it will 
doubtless be of interest to 
beck's lamp globe. many. It is made in about 

the same way as any globe for incandescent lighting; that is, it 
has all the air exhausted from the glass globe, and two wires 
which are extended to the inside of the globe through closely 
sealed places. Unlike other lamps, these ends are separated 




IN COMMON WORDS. 87 

a short distance, as may be seen by the view presented. 

In this form of the lamp, one wire enters on the side and ends 
with a ball of platinum ; the other enters at the bottom. 

Into the globe, before it is sealed, is put a small quantity of 
finely powdered and very dry charcoal ; also some nitrogen gas, 
and a very small amount of metallic, mercury in form of 
vapor. 

The gas holds the solid particles of carbon in suspension in 
the path of the electric current, which jumps across between the 
points of the wires. The current heats up these pieces of carbon 
to a white heat, but cannot burn them because they are in a 
vacuum. 

The mercury is intended to assist the current of electricity in 
passing between the ends of the wires. 

These globes are erected on the top of a stand which contains 
a coil of wire and what is called a " condenser," which is made of 
lead and paper sheets. The effect of the condenser and coil is to 
give the current, which comes from the battery located just below 
it, an intense power for heating the carbon. 

There is also a proposition to introduce the plan into the 
more general system of lighting, such as covering the houses, &c, 
in a district, from a central battery place. 

Probably the hopes of the majority of the people into whose 



88 ELECTRICITY 

homes the electric light will not find an entrance for a long time, 
will be realized by the perfection of the " Storage Battery T 

What is it? The reply will be simple : boxes of convenient 
size are made, for instance, 6 inches wide, a foot high and a foot 
long ; they are lined with lead so as to be water tight. Into these 
are put lead plates, on edge, separated by pieces of wood or 
similar material. 

These plates are pitted or full of holes, which are filled with a 
paste formed of red lead and other substances, and the whole is 
immersed in acidulated water. Every other one of the plates is 
strapped together with a lead band on one corner, and the inter- 
mediate ones on the other corner. A dynamo-electric machine is 
then connected by wire to these straps, and set in motion, and so 
sends a powerful current into the boxes. The effect of which is 
to form a coating of brown oxide of lead, on the plates connected 
on that side of the battery, making them powerfully electro- 
negative towards the metallic lead of the other plates. 

Without entering into the chemical action to a fine degree, 
suffice it to say that the electricity is sent by wires into these 
plates and accumulates in the oxide on them. It can, at pleasure, 
be drawn off in small or large quantities, and used for light or any 
purpose. 

At the present time the cost is considerable, but it is being 



IN COMMON WORDS. 89 

cheapened, and may soon be within the reach of the common 
people. It is necessary, however, to live along the route of a wire 
by which the storage batteries may be fed daily, or as they are 
exhausted. 

Their weight, at the present time, makes the carrying of the 
lead batteries to and from the dynamo for charging impracticable. 



Dynamo-Electric Machines. 

We now return to the subject of the best source of electric 
power for powerful currents. 

The " dynamo" is made up of two fundamental parts; the 
armature and the field magnets. While in the early forms the 
field magnets were made in part of steel pieces in the form of a 
horse-shoe, our description may well omit that form and only 
require the reader to look at the nature and make-up of the form 
most in use now for lighting and power purposes. 

Since the dynamo-electric machine is rapidly taking a place 
in mechanics, where it will have more or less to do with our every 
day life, the reader will do well to give it more attention and study 
than these pages afford. 



90 



ELECTRICITY 



Gramme's modification, in 1870, of what is called the ring 
armature, constructed by Page in 1852, was the beginning of the 
most important progress in the mechanical production of electricity. 
Since then applications of this mode of producing force have been 
a succession of rapid strides. In nearly all of the present leading 
forms of machines, it can be seen that the inventors have been 
close students under Gramme. With the use of this armature 
continuous currents are produced, while with previous machines 
only momentary ones were possible. 

The cut here presented 
shows the Gramme arma- 
ture in such a way as to 
allow its construction to be 
seen. 

The core or centre of it is 
made of a bunch of soft iron 
wires, and is wound about 
gramme armature. with wires covered with 

cotton to keep them separated — insulated. 

The ends of the little spools of wire are brought out and 
fastened to a flat copper strip laid upon the axle, which passes 
through the centre of the ring. This large spool is then mounted 
by its axle on proper bearings. The stationary magnets, called 




IN COMMON WORDS. 91 

field magnets, are placed closely up to this ring, but not touching 
it. Upon the axle a belt wheel is put so as to have steam engine 
power turn it very fast. 

As the ring is revolved a current is generated, and flows out 
with every change in its position. 

The current so made is carried out by brushes which press 
upon the terminal plates of the wires in the ring. These brushes 
are connected to the wires running out to the lamps. 

A view is here given of one of the improved Dynamos of the 
present time, and its general plan may be understood. 




WESTON DYNAMO. 



92 ELECTRICITY 

The general shape of the field magnets is that of a horse- 
shoe. Copper wire is wound around an iron centre and four of 
these spools are connected by the frame in pairs. Each pair is 
placed upon opposite sides of the ring armature, and the faces 
turned so as to bring the ring's surface very close all around. 

How the armature of this machine is made may be learned 
from the cut here presented, which shows the details on an 
enlarged scale. 

This core is made up, as may be seen, of discs of iron laid 
side by side, and then wound with a small amount of copper wire. 

Improvements have recently been made in many of the dy- 
namos by the employment of a separate governor, by which the 
intensity of the field is automatically regulated, so that in the 
event of any number of the lamps being cut out by accident, the 
others will not be affected by the strong current which other- 
wise would burn or do other damage somewhere in the circuit. 

The cut on page 94 shows one of these regulators. It also 
by a pointer shows just what work is being done. 



IN COMMON WO IDS. 



93 




ARMATURE OR CORE. 



94 



ELECTRICITY 




AUTOMATIC REGULATOR FOE WESTON ARC SYSTEM. 



IN COMMON WORDS. 95 

Another form of dynamo machine, for which a new principle 
is claimed, is the invention of Chas. E. Ball. 




BALL DYNAMO. 

While in the usual dynamo the armature is rotated between 
both poles of a field magnet, this one has two bobbins or arma- 
tures, each rotating near a separate field pole. 

From this machine both arc and incandescent lamps may be 
used at the same time, on separate circuits of wire. 



96 



ELECTRICITY 



Gas Lighting. 




GAS LIGHTED BY ELECTRICITY. 



IN COMMON WORDS. 



97 



Among the valuable uses of electricity, few are more pleasing 
than the lighting of gas. 

In theatres, churches, and such places, plate machines of 
a modified form are successful in lighting by a single flash several 
hundred jets of gas. 

Over the gas opening of 
each burner two wires are 
carried, the ends ol which 
point towards each other, 
and are but slightly separ- 
ated. The current is sent 
by wires from the machine. 
(A battery with a spark coil 
does the same work.) 

Through the house the 
wires are placed under the 
plaster and are hidden away 
out of sight. 

automatic burner. In residences the system 

is to run a wire from the cellar, or where the battery and spark 
coil are, to each gas fixture. 

The burners are of an especial kind, the most complete being 
what are called " automatic" (one is shown with part of its shell 
removed to show its parts). 




9 8 



ELECTRICITY 



Wires are run from this burner to a double press button on 
the wall, or suspended over the bedstead. By touching the white 
knob of the button, electricity is made to move a magnet which 
turns on the gas in the burner and makes at the same time a 
spark which lights it. Touching the dark knob of the button shuts 
off the gas in the burner in the same way. 

In another form where the burner can 
be easily reached, the gas is lighted by 
pulling a little chain which hangs down 
out of the globe. Two battery points 
are brought together and a spark created, 
and so the gas is lighted. 

In a complete system, the wires all run 
through an annunciator, where, in case ol 
accident to the burners or other parts, a 
little flag is dropped down, upon which can be read the name of the 
burner that is in trouble and at the same time a bell is rung call- 
ing the servants — all done by electricity. 

These burners are often connected with doors and windows 
and so fixed that when a burglar opens the house the gas is lit in 
his face and in the servant's room. 

Among other contributions to the comfort and conveniences 
of our homes the portable torch is fast occupying a place. In its 




GAS LIGHTED BY PULL- 
ING CHAIN. 



IN COMMON WORDS. 



99 



handle there is a sealed up battery and spark coil ; in its stem, a 
sparking point, which when held within the flow of the gas causes 
its ignition. 




Improvement has been made in this instrument by which the 
chemical battery and coil are replaced by an arrangement some- 
what similar to a dynamo machine. 

Among the various uses of electricity, one now occupying 
the attention of the theatrical managers is interesting. 

Incandescent lights are used for stars on fairies' heads, etc. 

The accompanying illustration shows various articles of 



ioo ELECTRICITY 

jewelry, each containing a small incandescent lamp, a full-sized 
sketch of which is appended. No. i is a hair-pin; 2 and 3 breast- 
pins; 4, the head of a cane; 5, a diadem for a tiara; and 6, a large 
gem, intended to be set in a necklace, for theatrical effects. The wires 




INCANDESCENT LAMPS IN THE FORM OF JEWELRY. 

are enclosed in a small supple cord concealed in the dress, and a 
switch within easy reach permits of turning the current on or off 
at pleasure. The practical use that we see in these jewels is that, 
in returning home late at night, they afford a ready means of 
brilliant illumination, which would aid in the finding of a lost 
object on one's way, and also the way to the key-hole, etc. It is 
said that the walking-stick, provided with a large diamond, affords 
sufficient light to read a newspaper by. If set with say a white 



IN COMMON WORDS. 



gem on one side and a red one on the other, it may be used for 
signaling to a distance, while the switch would enable a commun- 
ication to be carried on by means of the Morse alphabet. 

Considerable ingenuity is being exercised in creating more 
than brilliant jewelry, by surrounding miniature lamps with cut 
glass in many forms. By the light streaming out from the little 
electrically illumined carbon in the centre, many stage and 
scenic requirements are met, particularly in diadems, girdles and 
gems to be worn by foot-light sylphs. 

The cuts given, were described by The Electrical World 

recently. 

The little lamp in this cut has one side 

removed to show its inner construction. The 
ordinary incandescent lamp fully described 
in previous pages is used. In Paris instead 
of relying upon the accessibility of a dynamo 
current, they have a form of battery shown 
on page 102, worked by a bichromate of 
potash solution. 

The duration of incandescence varies nearly 
in the ratio of the capacity of the battery. The 
electric jewelry. sm allest, shown full size in the cut, is capable 
of maintaining illumination for twenty or twenty-five minutes; 




io2 ELECTRICITY 

while one twice the size, which may be carried by a belt 
attached to the outside cover, will maintain it for an hour. 



JEWELRY BATTERY. 

For theatrical effects of short duration, as many as twenty-five 
lamps have been kept going at the same time. The battery can 
also be recharged in a few minutes by renewing the solution. 

In electric toys, one of the electric manufacturing companies 
of this country has made a great success in well designed and 
cheap forms of machines operated by electric power. 

Among the handsomest being those representing engines, 
boats, etc., propelled by power from a carbon battery. 
These instruments not only amuse but teach the young the 



//V COMMON WORDS. 



103 




ENGINE RUN BY MOTOR. 

principles underlying electric motive power and mechanics. 
In the view given an electric motor is attached to and sur- 
rounds the axle on which the balance wheel is run. 



io4 ELECTRICITY 



The Electro-Motor. 

Electro-motive power is produced by the great attractive 
power of the electro-magnet; that is a magnet formed by passing 
a current of galvanic electricity through a bar of soft iron. 

The first electro-motor, large enough for any practical use, 
was constructed by the celebrated Russian, Philos Jacobi. 

In 1 839, by the use of one of these motors, he propelled a boat, 
carrying ten persons, at the rate of four miles an hour. Instead 
of the dynamo, he obtained his electrical force by means of a 
powerful galvanic battery. 

In Denmark, a patent was obtained in 1849 by Mr. Hijorth, 
for an electro-motor engine of ten horse power. This was the 
most powerful then in existence. 

The large motors now used are run by dynamo machines. 
In the dynamo, as was explained, the rapid revolution of the 
armature produces the electrical force ; but in the motor, the 
electrified magnet causes the revolution of the armature. The 
motor is, therefore, the reverse of the dynamo. 



IN COMMON WORDS. 105 

The electric motor is made by putting a ring of soft iron, or 

and is made to revolve by electric motor. 

passing a current of electricity through the magnet. 

In one of the forms lately presented, there is a hinge in the 
back or curve of the magnet, and the armature is made to revolve 
rapidly or slowly by bringing the poles or ends of the magnet 
near it, or removing them from it by means of a thumb-screw. 
(Generally the speed is controlled by regulating the amount of 
current fed to the motor.) A wheel is placed on the end of the 
armature, and in this way a sewing or other machine is belted on 
to it and set in motion. 

The motor has the advantages of being noiseless in its action, 
can be easily moved from one place to another, is safe, easily con- 
trolled, and free from dirt. 

It is very finely adapted to the manufacture of mathematical, 
optical, and other delicate instruments. 

The impression that the great attractive power of the electro- 
magnet could be profitably applied to machinery was so great at 



io6 ELECTRICITY 

one time that an appropriation of $20,000 was made by Congress, 
and one of $120,000 was made by Russia to experiment in this 
direction. 

A great many machines w r ere invented for using it as a motive 
power, but in no case was it found to be so economical and efficient 
as steam. 

What the future will bring forth no one can safely predict. 
Dynamo machines are run by steam, gas, or water power; and 
of course do not produce as much power as the engine exerts in 
running them, because there is necessarily some loss from friction. 

Every time power is transferred from one machine to another, 
some of it is lost. 

In motor work, first coal is burned to run the steam engine, 
which by belts or by direct connection of the shaft, revolves the 
bobbin of the dynamo electric machine, and thus creates a current. 
The motor is then connected by wires to this current which causes 
its armature to revolve and do the work by directly turning the 
drill or by further belting, putting in motion other forms of 
machinery. It is therefore readily seen how, in so much re-trans- 
mitting of the power from the coal pile to the drill or sewing 
machine, much loss must necessarily be sustained. 

Street railways are adopting this form of power and in 
Cleveland seem to be successful. 



IN COMMON WORDS. 107 

In one system proposed, the rails are used to carry the 
electricity from the home station. All along the road the cars get 
the power by carrying the current through their wheels to motors 
on the cars. The motor causes the car axle to revolve and so 
runs the car. 

The fact that electrical force can be conducted great distances 
suggests the possibility of utilizing waterfalls to run the dynamo 
to generate the electricity, which can be conducted to motors in 
factories miles distant. 



Conclusion. 

As an applied science, electricity has not yet reached its 
teens. Slumbering for ages, it has suddenly awakened to a new 
existence, and has developed during the last ten years in a manner 
truly startling. In fact it has become a growing necessity of the age. 

In the form of automatic signals, it warns the engineer of 
impending danger. As an electric organ, it is made to play sweet 
and delightful music. As a flash light, it illuminates the dark face 
of the deep for miles ; and in various other ways, many of which 
have been explained, it supplies the wants of oui advanced civili- 
zation. 



108 ELECTRICITY, 

The International Electrical Exhibition, given in the city of 
Philadelphia under the auspices of Franklin Institute, displayed 
in the grandest manner, the power, production, present and 
possible uses of electricity that the world has ever seen. 

Yet who will say that the next decade will not produce a 
grander one having all the present developments as a nucleus ? 

The human intellect is continually unfolding and developing 
its powers, so that the impossibility of to-day becomes the possi- 
bility of to-morrow, the probability of day-after-to-morrow, and 
an accomplished fact the succeeding day. 

The Almighty has stored the air, the sea, and the land with 
forces which were permitted to slumber, until He allowed them to 
be called into activity, as they were required to meet the wants of 
successive generations. 

Electricity is but one form or manifestation of this force ; and 
judging from the past decade, we are justified in the belief that 
during the next, the application of it to the various wants of 
society will far exceed our most sanguine expectations. 

If the reader has acquired even a partial knowledge of the 
subject, the writers have been amply repaid for their toil; and 
especially so, if this casual view incites the reader to more careful 
study of this attractive and fruitful branch of science. 

THE END. 



— THE- 



T^eMm SySkmA of SieMc £i$hUn§. 



In efficiency, reliability , perfection of auto- 
matic regulation, and thorough workmanship 
in the construction of all parts of the apparatus, 
these systems are far superior to any other 
system of Electric lighting. 

We make a full line of dynamo machines, 
electric lamps, and accessory devices for three 
complete systems: the Weston Arc System, the 
Weston Incandescent System for la^rge lights 
of 125 to 300 candle power, and the Weston 
Incandescent System for Standard 16 candle 
power lights. 

Full information with prices and estimates 
will be furnished upon application. 

The United States EleGtriG Lighting 6o. 

59 Sj- 61 Liberty St., NEW YORK. 



The American District Telegraph 
Company of Philadelphia. 



FOURTEEN DISTRICT OFFICES IN THE CITY. 



The call boxes of this company provide for Police, Five, 
and JMessengev service, and in connection with the latter enable 
subscribers to summon at any hour a Carriage or a Physi- 
cian ; also to have Letters, Cards, etc., delivered to any part 
of the city. 

Burglar Alarm connections made with any of the offices 
of the company. Temporary Alarm connections provided 
for residences unoccupied during the summer season. 

Circulars and Books addressed and distributed to all 
parts of the city. 

Telegrams sent to all parts of the world. 



EXECUTIVE OFFICES: 



No. 208 West Washington Square. 



NOVELTY ELECTRIC CO., 

Store and Pactory, Pifth and Locust $ts., 
PHILADELPHIA, PA. 



J. Chester Wilson, - - - General Manager. 



MAN UFA CTURERS, 

CONTRACTORS, 

AND DEALERS IN 

ELECTRICAL SUPPLIES 

OF EVERY DESCRIPTION. 



Bells, Toys, 

Batteries, 

Buttons, Wire, 

Telegraph, Telephone, 

Electric Light 



EQUIPMENTS. 



SEND FOR CATALOGUE. ASK FOR PRICES. 



ELECTRICITY 



T 




IN COMMON WORDS. 



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